1. Field of Invention
The present invention relates to a radio frequency identification (RFID) communication system and method; more particularly, the present invention relates to a RFID communication system and method that send designate messages through certain channels so as to dynamically actuate a receiving mode of an active RFID tag.
2. Related Art
The radio frequency identification (RFID) system consists of a reader and an RFID tag. Usually the RFID tag is either active or passive, mainly depending upon whether the RFID tag has electrical power. A powered RFID tag is active; otherwise, it is passive. Either active or passive, the RFID tag is used to transmit data to the reader for further processing. For example, the reader receives data from the active RFID tag and transmits them to the subsequent application system, thereby determining he location of the RFID tag or checking identification.
Some manufacturers propose RFID tag designs that can provide a receiving mode for receiving commands emitted by the reader, so that the command can be executed. However, using the power inside the active RFID tag for the receiving mode greatly reduces the running time thereof. Therefore, even though the above-mentioned method enables the active RFID tag to have both transmitting and receiving abilities, the power consumption is also greatly increased. This problem is particularly serious when the RFID tag is in the receiving mode for a long time.
In summary, the active RFID tag in the prior art always has the problem of too much power consumption in the receiving mode. It is therefore imperative to provide an improved technique to solve the problem.